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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47830 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index 7bc50e5aa39d87dcc8e835a10b5acbb379102d7c..55baf8d270ade8a0387ba6f00c02d383fc5b9373 100644 (file)
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -714,3 +714,42 @@ GCC compiles this into:
 which is more efficient and can use mfocr.  See PR642 for some more context.
 
 //===---------------------------------------------------------------------===//
+
+void foo(float *data, float d) {
+   long i;
+   for (i = 0; i < 8000; i++)
+      data[i] = d;
+}
+void foo2(float *data, float d) {
+   long i;
+   data--;
+   for (i = 0; i < 8000; i++) {
+      data[1] = d;
+      data++;
+   }
+}
+
+These compile to:
+
+_foo:
+       li r2, 0
+LBB1_1:        ; bb
+       addi r4, r2, 4
+       stfsx f1, r3, r2
+       cmplwi cr0, r4, 32000
+       mr r2, r4
+       bne cr0, LBB1_1 ; bb
+       blr 
+_foo2:
+       li r2, 0
+LBB2_1:        ; bb
+       addi r4, r2, 4
+       stfsx f1, r3, r2
+       cmplwi cr0, r4, 32000
+       mr r2, r4
+       bne cr0, LBB2_1 ; bb
+       blr 
+
+The 'mr' could be eliminated to folding the add into the cmp better.
+
+//===---------------------------------------------------------------------===//